Hello, Thank you for your query. Haldol is an antipsychotic drug that decreases excitement in the brain. Haldol is used to treat psychotic disorders like schizophrenia, to control motor(movement) and verbal. Haldol treated in elderly patients with dementia-related psychosis are at an increased risk of death. For patient who has received chemotherapy-induced nausea and vomiting, breakthrough, maybe used an adjunct to standard antiemetic regimens for breakthrough nausea/vomiting. For acute manic or mixed episodes and acute hypomania , haldol may worsen depressive symptoms. It is not recommended for the treatment of acute bipolar major depression or for maitenance in bipolar disorder. Deliriun and hyperactive antipsychotics maybe used as short-term adjunctive treatment is distressing symptoms. The severe side effect of haldol include death in elderly, prolongation of the QT heartbeat interval, tardive dyskenesia(involuntary movements), irreguklar heartbeats, mental status change.. Long term use or high dose of haldol can cause a serious movement disorder that may not be reversible. Symptom of this disorder include uncontrollable muscle movements of your lips, tongue, eyes,face, arms, or legs. The longer you take haldol the mor elikely you are to develop a serious movement disorder. The risk of this effect is higher in women and older adult. Talk to his doctor again about option of treatment for his condition. Bring him to see his doctor if he has sudden mood chnages, agitation, hallucinations,twiching or uncontollable movements of his eyes, lips, tongue, face, arms, or leg, stiffness in his neck, tighness in throat, trouble breathing or swalloing, sudden weakness or ill feeling.... Hope I have answered your query. let me know if i can assist you further. Best regards, Dr. Heang Chan Raksmey, General and Family Physician.